UNDP–GEF CSH ProjectMinistry of New and Renewable Energy

Government of India

Volume 4Issue 1

July–Sept 2016

CONCENTRATED SOLAR THERMAL PROGRESS IN INDIA

SUN F CUS |July –September 2016| 32 | SUN F CUS | July–September 2016

12Feature 2

Chief PatronShri Upendra Tripathy, Secretary, MNRE

Editor-in-ChiefShri Santosh D Vaidya, Joint Secretary, MNRE

Editorial BoardMr S K Singh, Director, NISEDr R P Goswami, Director, MNREDr S N Srinivas, PO, UNDPMr Abhilakh Singh, GM, IREDADr A K Singhal, NPM-CSHP, MNREMr Shirish Garud, Director, TERI

Content CoordinatorsMr Rahul Udawant, MNREMr Kumar Abhishek, MNRE Mr Chinmay Kinjavdekar, TERIMr Sarvesh Devraj, TERI

Production TeamMs Anushree T Sharma, TERIMr R K Joshi, TERIMr Santosh Gautam, TERI Mr Raman Kr Jha, TERIMr Aman Sachdeva, TERI

Produced and Published byProject Management UnitUNDP–GEF project on CSHMinistry of New and Renewable Energy Government of India, New DelhiWeb: www.mnre.gov.in&TERI Press TERI, Darbari Seth Block, IHC Complex Lodhi Road, New Delhi – 110 003Tel: +91 11 2468 2100, 4150 4900Fax: +91 2436 3035, 2436 2288Email: teripress@teri.res.in

DisclaimerThe views expressed by authors including those of the editor in this newsletter are not necessarily the views of the MNRE and the publishers.

Printed atSVS Press116, Patparganj Industrial Estate, New Delhi – 110 092, India

Cover image: CPC system installed at Kandla by VCare Global.

Volume 4 • Issue 1 July–September 2016 a quarterly magazine on concentrated solar heat

INside...

Message from Minister 3

Message from Secretary 4

Editorial 5

Special Feature

• Experiences on Compound Parabolic Concentrators Installed at Manufacturing & Dairy Units for Process Heat Applications 6

Features

• Solar Dish Cooker for Community Cooking 9

• India’s First Poly-Generation Concentrated Solar Thermal System for Industrial Heating 12

• Solar Thermal Technologies Flourishing at Leh 17

Case Study

• Compound Parabolic Concentrators Used for Industrial Process Heating in Kandla 15

International Feature

• Open Loop Tracking for Parabolic Trough Collectors 20

Events 22

Forthcoming Events 23

CONTENTS

17Feature 3

MESSAGE

India is a country with rich solar resources and Government of India has modified Jawaharlal Nehru National Solar Mission (JNNSM) target of 20 GW solar power to ambitious 100 GW solar power by 2022. Government's emphasis on solar energy is due to the fact that it produces clean and emission free energy while reducing country's dependence on fossil fuels. Apart from power generation, solar energy can also play an important role in saving fuel used for heating and cooling applications in industrial, institutional and residential sectors through Concentrated Solar Thermal (CST) technologies. The Ministry of New and Renewable Energy (MNRE) has initiated a couple of projects in association with UNDP and UNIDO to promote CST applications through financial and fiscal support to users and technology providers/manufacturers. MNRE has also taken steps to develop Renewable Energy (RE) Policy in this regard.

CST technologies, both in India and on global scale, are in a nascent stage but have huge potential to impact carbon footprint of global industrial sector in a significant manner. For a developing country like India, CST technologies offer very attractive proposition. The clean and emission free source of energy will help reduce fossil fuel consumption significantly. This will also reduce carbon footprint of industrial sector, assisting India's commitment to reduce its greenhouse emissions. The Government of India (Gol) through Bureau of Energy Efficiency (BEE) has initiated a massive programme for energy conservation across all sectors and promotion of CST technologies to further reduce fossil fuel consumption is next logical step in this direction. These technologies offer opportunities for development of indigenous technologies which can create local jobs and take forward 'Make in India' initiative launched by the Hon'ble Prime Minister Shri Narendra Modi.

The MNRE has recognized this potential and has taken systematic efforts for development and support of CST sector. These efforts have culminated into installation of approximately 42,000 m2 of aperture area of CST systems into community cooking, process heating and cooling applications. Publication of SUN FOCUS magazine is one of such initiatives by MNRE, which is spreading awareness about CST technology all over the country.

I wish SUN FOCUS well for its continued journey and further progress.

Shri Piyush Goyal

4 | SUN F CUS | July–September 2016

Editorial

F rom the editor’s desk...

Dear Readers,

I am pleased to be part of clean technology such as concentrating solar thermal (CST) which plays an important role in power and heat generation in India to accelerate the decarbonisation in the commercial and industrial process heat generation. It is evident that rapid deployment of CST in India will contribute to enabling sustainable energy supply and environmental securities over the next decades. The success of deployment of CST technology will also allow Indian power and heat generators to strengthen their competitiveness in the context of intensified global constraint of carbon emissions.

I also glad to state that SUN FOCUS completes an important milestone with the completion of three years. Since 2013, SUN FOCUS has been providing potential information on CSTs such as policy, technology developments, new applications, and national & international scenario.

With the advent of fourth year, I present you the thirteenth issue of SUN FOCUS magazine with you all. This issue of SUN FOCUS is themed as “Concentrated Solar Thermal Progress in India” covering various recent and interesting developments.

The special feature of this issue covers a really promising technology–compound parabolic collectors (CPC) by SUNBEST. The article shares experiences on compound parabolic concentrators installed at manufacturing & diary units for process heat applications. Another interesting article “Solar Dish Cooker for Community Cooking”, is about the concentrator developed by Dr Ajay Chandak for the community cooking purpose.

The magazine also features article on concentrated solar thermal based poly-generation system generating hot water and thermic fluid heating, and introduces CPC collector technology development undertaken by VCare Global. You will also find a brief write-up on the overall solar thermal sector developments in Leh area and an article from Concentrated Solar Power developer Atria, about the tracking and control system for parabolic trough collectors.

I believe that you will find this issue filled with very relevant and interesting information on CSTs and look forward to your valuable contribution or inputs for the magazine.

Sd/-

Santosh D. Vaidya

Joint Secretary, Ministry of New and Renewable Energy & National Project Director, UNDP–GEF CSH Project

MESSAGE

Concentrated Solar Thermal (CST) sector is very promising for India; firstly, due to costly fossil fuels and increasing stress on fuel source, such as wood and secondly, due to adequate availability of solar resource potential (5–7 kWh/m²/day) in the country. Food, beverage, dairy, textile, machinery, and pulp and paper industries, where predominant heat requirement is below 250°C, are most suitable for CST implementation.

CST sector in India has progressed well since the last few years, but is still far from commercial maturity. A lot of development is required in terms of technology reliability, awareness generation, and improvement in overall perception of the technology for user industries as well as financial institutes. It is also important to improve application of CST technologies to large, energy-intensive industries and smaller MSME industries. The MSME sector has tremendous potential for CST in India, provided customized technology solutions are available and industry-specific issues, such as shortage of space and lack of capital for high upfront costs are catered.

Ministry of New and Renewable Energy has made efforts to grow and develop the CST sector for a long time. It supports various initiatives covering all important aspects of the sector. There are efforts towards standardization and indigenization of important CST technologies, awareness generation of various stakeholders, such as user industries, financial institutions, and improvement in performance reliability of CST technologies and of course, financial incentives through various schemes.

To accelerate the growth of CST technology, the Ministry is also implementing a UNDP–GEF supported project on “Market Development and Promotion of Solar Concentrator based Process Heat Applications in India”. The objective of the project is to promote and commercialize Concentrating Solar Technologies for industrial process heat applications in India and facilitating the installation of 45,000 m² of installed solar collector area by March 2017, through demonstration and replicated projects.

The publication of SUN FOCUS is part of MNRE–UNDP–GEF project, which is an initiative for reaching out to various stakeholders of CST sector.

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SUN F CUS |July –September 2016| 76 | SUN F CUS | July–September 2016

Figure 1: Components of CPC Technology

Figure 2b: After Solar InterventionFigure 2a: Before Solar Intervention

Special Feature Special Feature

Compound Parabolic Concentrator, also known as CPC solar collector, is a

recent innovation in the solar field. This technology combines the high efficiency evacuated system plus solar radiation concentrating system with copper U-tube aluminium fins for heat transfer (Figure 1). Even in low radiation, it can generate pressurized hot water above 100°C. Unlike other evacuated tube systems, water passes through a copper-U tube with aluminium fins ensuring high heat transfer, ruggedness, and long life of the unit. CPC has an efficiency above 60 per cent. The system operates as follows:

$ The solar panels will be mounted on the south-facing roofs of the factory.

$ DM water in closed loop in these panels will be pressurized and circulated by this arrangement, even if low radiation heat from sun’s heat could be tapped.

$ A pump will be used to circulate

the pressurized water around

90°C–120°C.

CPC at TTK Prestige Roorkee Manufacturing UnitTTK Prestige Ltd, part of the TTK

Group, has emerged as India’s

largest kitchen and consumer

appliances and healthcare

company, catering to the needs of

homemakers in India and abroad.

Today, the TTK group spans 30

product categories, across 7 group

companies, and a turnover that crosses `30 billion. TTK Prestige had set up a manufacturing unit at Roorkee in Uttarakhand for manufacturing of kitchen electrical appliances and pressure cookers.

Overview

The manufactured pressure cookers are to be cleaned for oil and other impurities in specialized

different baths (Picture 1). The hot water at 90°C–95°C is used for the process and diesel-fired thermal oil heats water indirectly, using a heat exchanger in a 5 kl insulated water tank at 90°C–95°C. To reduce the fuel consumption, the factory had installed around 200 m2 CPC system to meet the process heat. The 60 special types of CPC-18 solar collectors are mounted on

EXPERIENCES ON COMPOUND PARABOLIC CONCENTRATORS INSTALLED AT MANUFACTURING & DAIRY UNITS FOR PROCESS HEAT APPLICATIONSC Palaniappan1, H T Rajan2 and Muthuswami3

1 CEO, Sun Best (P) Ltd, Theni, Tamil Nadu; Email: info@sunbest.in

2 Chief Manufacturing Officer, TTK Prestige Ltd, Bangalore; Email: htr@ttkprestige.com

3 Joint General Manager, Hatsun Agro Product Ltd, Chennai; Email: muthuswami@hatsun.com

the factory’s open flat terrace. The system is expected to save around 18,000 litres of diesel/year and 48 tonnes of CO

2. CPC collectors can

be effectively used for 7–8 hours/day which almost covers entire sunny period.

System Description

Around 60 CPCs, each with 18 tubes and reflectors, are installed on the factory open terrace. A closed loop with solar collector array, consisting of series and parallel connections of CPC with an expansion tank, pump, and other accessories like pressure and air release valve, pressure balancing valve, etc., are formed in a closed loop with a 5 kl tank (Figures 2a & 2b). The hot water from the 5 kl tank is taken to the process. During non-sunny period, the 5 kl tank could be heated by diesel-fired thermic oil heating system. Based on the actual data collected from November 2015 to September 2016, the system saved 16,740 litres of diesel.

The performance of the new concentrating technology has been proved at Roorkee, which typically has very low radiation levels in winter. Consequently, the company has applied for another CPC project of 262 m2 for the Roorkee factory.

Challenges

The company preferred to go for CPC collectors mainly to overcome fog in winter and the low radiations in winter. The system has so far saved 16,740 litres of diesel. The 5 kl storage helps the operation hours of factory to go beyond sunny hours.

CPC at Hatsun Agro Product Ltd Salem Dairy UnitHatsun Agro Product Ltd is one of India's largest private sector company in the dairy industry. Milk from select fine quality cows is collected from over 3 lakh+ farmers across 8,500 villages. The company has set up dairies in 10 locations, possessing state-of-the-art facilities and international know-how to enable creation of excellent quality products meeting highest norms of hygiene and health. These dairy ingredients are being exported to 38 countries in the US, Middle East, and South-East Asian markets. The company, producing and marketing a wide range of dairy products, holds various quality standard certifications, including the prestigious ISO 9001 and ISO 22000. Arun Ice creams, the largest-selling ice cream seller in south India, and Arokya Milk are immensely popular

across millions of households in south India.

Overview

The Salem plant at Hatsun Agro Product Ltd requires 35 kl hot water at a temperature of 90°C–95°C for process heat in the ice cream plant and around 40 to 50 kl for the boiler feed water (Picture 2). Presently, hot water for processing is produced using steam with a plate heat exchanger (PHE). The average coal consumption/day is 11.3 tonnes in the 8 tonne boiler. The site at Salem, Tamil Nadu, receives annual average of 5.19 kWh/m2/day of solar radiation (as per NASA). Based on the energy demand, 220 CPC-18 collectors of 3.28 m2 area are installed to provide around 25,000 litres hot water around 90°C–95°C to reduce coal consumption around 194 tonne/per year. Solar CPC system to provide hot water of capacity 25,000 litre/day at a temperature of 90°C during sunny period to bring down the coal consumption and pollution; better pollution control; and reduction in CO

2

emission along with better efficiency in avoiding water to steam in boiler and again steam to 90°C water by PHE.

Aluminium finAluminium fin

Vacuum tube Vacuum tube

U-type Copper branch

Hot terminalHot terminal

Cool terminalCool terminal

Pump

Thermicfluid

heater110 °C

H.E

5 KL

Storagetank

Diesel burner

To applicationfor process heat at 95 °C

Return from application

Pump

Pump

Thermicfluid

heater110 °C

H.E5 KL

Storagetank

Diesel burner

To applicationfor process heat at 95 °C

Return from application

D A

Solar Panels Array

Backup heating

Pump

F

Picture 1: CPC Solar Collectors Installed at TTK Prestige for Hot Water Generation Required for Cleaning Impurities

SUN F CUS |July –September 2016| 98 | SUN F CUS | July–September 2016

Figure 3a: Before Solar Intervention Figure 3b: After Solar Intervention

Special Feature Feature 1

SOLAR DISH COOKER FOR COMMUNITY COOKINGDr Ajay Chandak1 and Gulu Advani2

Identified as the world’s biggest and most successful effort, the Mid Day Meal Scheme is

operational in 1.2 m rural schools in India. Fuel used in these schools is mostly firewood or LPG. However, providing LPG to most of remotely located schools is a huge task. The Asian and African countries are blessed with ample sun and so, switching over to ‘solar cooking’ is a viable option. In this regard, the Ministry of Human Resource Development, Government of India, has budgeted Rs. 3000 crore for provision of community solar cookers for 5 lakh schools in the Twelfth Five Year Plan.

The use of individual or family-sized cookers is restricted due to limitations of space and cooking timings, but community cooking does have a huge market potential, especially in India. Temples, old age

homes, residential schools, hotels, public health centres, aanganwadis, mid day meal schemes in schools, and the border security forces, are the primary areas where community cooking is practiced on a large scale and many million meals are prepared on a daily basis. In recent years, development of community dish cookers such as SK-23 and PRINCE-40 have shown great potential in energy saving and mass deployment of technology.

SK-23 Community Dish Cookers: Review of InstallationSK-23 is a simple dish cooker of 2.30 m diameter with 4 m2 aperture area. Cooking tests, conducted on these cookers, by the regional test center of the Government of India at the University of Pune showed that the cookers are capable

of cooking a mid day meal for 50 students in just 1 hour. More than 500 community dish cookers were installed for private users as well as government organizations through various manufactures. These included the world’s largest installation with 360 dish cookers, consisting of a total aperture area of 1,440 m2, installed at 160 tribal residential schools in Maharashtra (Picture 1). At present, these systems are cooking meals for more than 25,000 students, saving 54 tonnes of LPG equivalent, i.e., around 150 tonnes of carbon emission reduction per year. Despite the success of the SK-23 community dish cookers, large-scale dissemination was difficult, as the dish of 2.3 m diameter was fabricated in single piece, was difficult to transport and required an expert installation team.

1 SSVPS BSD College of Engineering, Deopur, Dhule; Email: renewable.consultant@gmail.com

2 Director, Elektromag Group of Industries, Unique, Mumbai; Email: lighting@elektromag.com

Picture 1: SK-23 Installations at Hotel Emerald Park, Nasik (Left), and at a Tribal School in Nandurbar District (Right)

System Description

The factory has a large south-facing metal roof over the ice cream storage facility. The 220 CPCs are divided into 110 each as a one full system and fixed on the roof of the factory with metal support. A primary closed loop is formed with solar collector array consisting of series and parallel connections with an expansion tank, pump, plate heat exchanger (PHE), and other accessories like pressure and air release valve, sensors, and others (Figures 3a & 3b). The cold water passes through the PHE in the secondary loop and get heated up to a temperature of around 90°C to 95°C and it is taken to the process. Based on the actual data collected for 15 days in the month of September 2016, a savings of 672 kg/day of coal was observed (some of the days are cloudy, rainy, and partly sunny).

The company has been taking major initiatives in renewable energy by installing 22MW wind mill and 1,500 kWth/day solar CPC heating system and includes future plans

Temperature25–30 °C

Temperature95 °C

Temperature95 °CSteam at 3 par pressure

from Boiler

40 kLCold

Watertank

Pump

Pump

PHE

PHE

Condensate

Condensate

Steam at 3 par pressurefrom Boiler

To Process Heat

To Process Heat

Set of 220 Panels CPC Collectors

PumpPump

Cold water to solar

Hot water from solar

PHECold water Makeup

water

Boiler feedwater PHE

Steam at4 bar

Hot water forprocess at 95 °C

Hot water forprocess at 95 °C

Condensate water

of introducing more solar, thermal as well as large megawatt SPV projects for captive power needs.

Hatsun Agro Product Ltd is the first CPC unit for dairy industries in the country.

Challenges

The requirement of hot water for processing starts early morning at 4 a.m. and continues for a few times during the day and in the night. Hence, a 21 kl insulated storage has been incorporated to hold the hot water. The other challenge is the distance of process application from the hot water generation point which is 300 m and drop of 3°C–50°C was observed during this transfer. Due to the 15 m height of the roof, the installation team had to face major hardships during

installation.

Picture 2: Hatsun Agro Product Ltd Plant Uses CPC for Hot Water Feed into Boilers

10 | SUN F CUS | July–September 2016

Feature 1 Feature 1

SUN F CUS |July –September 2016| 11

PRINCE-15 and PRINCE-40 solar cookers were also used by a Dutch team in the world’s first ever solar trek in Nepal (Picture 4). All food, for the trekkers, at all the trekking sites, was cooked on these solar cookers. These solar cookers proved their worth even at elevation of 4000 masl and also established the fact that they are easy to transport and assemble even in the hilly terrain of Himalayas.

ConclusionThe new DIY kit design of

PRINCE-40 paneled solar

concentrator has the potential

to create wonders in community

cooking in terms of being one of

the cleanest cooking methods,

reducing emissions to large extent,

and hygienic.

Trials also show suitability of

the technology for applications

like autoclaving at rural public

health centres. Applications like water distillation and bakery can be practiced as micro enterprise to generate revenue for rural folks and improve utilization of the concentrator.

One small version of the square dish, already available as PRINCE-15, as domestic dish cooker of 1.5 m2 can be promoted in rural areas for cooking for families, especially in areas where cooking fuel like firewood, LPG, kerosene, etc., is scarce. In the deserts of Rajasthan, Kutch, and Ladakh, these domestic as well as community solar cookers are blessings in disguise.

Technology requires financial support from the government and by other means such as carbon funding in order to improve viability of the projects. Widespread demonstrations and pilot projects are also needed for the prospective users to acquire a first hand feel of the system. A wider network of manufacturers, dealers, and entrepreneurs to improve availability of the new

designs needs to be developed.

Picture 4: PRINCE-15 and PRINCE-40 Solar Cookers in First Ever Solar Trek in Nepal

Development of PRINCE-40 ConcentratorIn order to overcome the limitations of SK-23 concentrator dish, a new compact design, PRINCE-40, was developed. Herein, all construction members of the dish are of same geometry and hence, it is possible to design the dish as knock down assembly which can be assembled onsite. Although this design, a square paraboloidal dish, also required an expert team for installation, it did resolve the transportability issue of SK-23. The cooking test showed that PRINCE-40 solar concentrators are better in terms of performance than SK-23.

Adoption of PRINCE-40 Concentrators for Community Cooking

After successful laboratory and field tests, PRINCE-40 technology was disseminated to a few prospective entrepreneurs. The first sizable project came up at Madhya Pradesh Samaj Seva Samiti (MPSSS), a residential facility for tribal students at more than 200 locations. Initially, two installations were made and reviewed by cooks from different schools (Picture 2). On recommendations of the cooks, a total of 42 PRINCE-40 community cookers were installed to serve more than 2,500 children. The feedback received from end users showed a high level of satisfaction.

The WOTR (Watershed Organisation TRust) which expanded its scope of work beyond watershed development to rural energy needs approached the PRINCE Group for appropriate technology options. Encouraged by the experience of MPSSS, WOTR initially placed an order for four

systems and meticulously exposed their prospective users to these systems. Post positive response from the user community, WOTR also installed 23 systems, catering to more than 1,300 children in Sangamner tehsil of Maharashtra, later, 10 PRINCE-40 solar cookers were installed by WOTR in Madhya Pradesh and Chhattisgarh (Picture 3). The projects by MPSSS and WOTR have shown the possibility of adoption of this technology on a large scale for community cooking applications.

Experimenting with PRINCE-40 Concentrators beyond Cooking

Use of solar concentrator for sterlisation can prove to be very useful, especially in rural public health centres where availability of the power is very uncertain. It is possible to sterilize the autoclave with contents, when sun is available, and store the ready autoclave for 2–3 days. Such successful tests have opened doors for deployment of solar concentrators in medical applications.

Development of Segmented Dish Version of PRINCE-40Fabricated version of PRINCE-40 solar cooker has 42 structural strip members, bolted together to form structure of the dish to which the reflectors are tied. The geometry in which the fabricated dish is kept was replaced by sheet metal panels. These 8 panels form the same geometry of fabricated dish keeping center open. The open centre allows passage for the wind and prevents toppling of the solar cooker. In the new design, reflectors are factory-fitted and this makes the design a truly DIY (Do It Yourself) kit. As the dish segments are manufactured on dies, the geometry is consistent and production time is low; process of assembly takes only two hours for two people.

The new design of paneled PRINCE-40 concentrator was also tested at the regional test center and at 10 different engineering institutes. The results of these tests are visible in the figure below.

Cooking time

5 kg rice 60 minutes

100 eggs 80 minutes

5 kg potatoes 60 minutes

3 kg pulses 60 minutes

Picture 3: Tribal Workers Installing PRINCE-40 Concentrators and Cooking in Action

Picture 2: PRINCE-40 Solar Cookers Adoption by Coimbatore Corporation for Mid Day Meals in Schools

SUN F CUS |July –September 2016| 13

Figure 1: Schematic Diagram of Hot Air Generation Using CST System

Feature 2Feature 2

Concentrators that concentrate incoming solar radiation to heat up thermic oil up to 200°C which generates hot air at up to 140°C through radiator.

CST-Based SystemThe CST system is based on state-of-the-art high efficiency paraboloid dish concentrator based system, the MWS Solar Field™. The MWS Solar field™ has been designed, engineered, and commissioned by Megawatt Solutions Pvt Ltd, an MNRE-channel partner for CST industrial process heating solutions. The system is based on fully two-axis tracking paraboloid dish concentrators with high concentration ratios and low ground foot print. The system was commissioned in June 2016 and is operational since July 1, 2016.

The MWS Solar Field™ is engineered to provide hot air indirectly by heating thermic oil in the solar field, which exchanges

INDIA’S FIRST POLY-GENERATION CONCENTRATED SOLAR THERMAL SYSTEM FOR INDUSTRIAL HEATINGTara Parthasarathy1, Indira Sudararajan2 and Siddharth Malik3

Ultramarine & Pigments Ltd (UPL) is one of the largest pigment and surfactant

manufacturing companies of Indian origin. At the factory located in Ranipet, Tamil Nadu, the industrial process requires Special Kerosene Oil (SKO)-based thermic oil heating system for drying of the product pigment. The company first explored hot air-based natural drying to reduce load on SKO dryer and reduce SKO consumption. Although SKO

consumption was reduced to some extent, the drying rates were too slow and led to a large inventory of pigments and loss of productivity. The company then decided to explore technologies which will enable saving SKO consumption and enhancing the production efficiency and productivity.

Post market research, UPL decided to adopt solar-based thermic oil heating. The technology was two-axis tracking paraboloid dish concentrator

system (Picture 1), developed by Megawatt Solutions (MWS), an MNRE-channel partner for turnkey delivery of CST technologies and solutions to reduce fossil consumption in process and thermal applications in industries. MWS studied customer’s drying requirement and designed a solution for enhancing their drying with minimum fuel consumption. The solution consisted of six dual- axis tracking based completely on automated Solar Paraboloid

T2

T3

T1

Solarwater

Hot airgenerator

Pump

Hot air to tunnel

V1 V2LocationDelivery

Capacity

Dish numbers

Commissioning

Ranipet, Chennai55 000 Kg of hot airat upto 130 °C15 lac kcal per day

6 Nos. of M95 dishes

June 2016

1 Joint Managing Director, Ultramarine & Pigments Ltd., Chennai; Email: syndet@ultramarinepigments.net2 VC & Managing Director, Ultramarine & Pigments Ltd., Chennai; Email: syndet@ultramarinepigments.net3 Managing Director, Megawatt Solutions Pvt. Ltd., New Delhi; Email: smalik@megawattsolutions.in

energy with the air circuit in which air is fed at ambient temperature and raised to a temperature of 130°C for feeding into tunnels (Picture 2) to displace SKO conventionally used for drying. The operation of the system is shown in Figure 1.

Along with heating thermic oil to 200°C for hot air generation,

the system is also configured to generate hot water at 90°C for boiler feed water heating. This secondary application is designed so that solar energy is completely utilized and there is no wastage even during peak sunny hours. The salient features of the project are enumerated in Table 1.

Picture 1: CST System for Pigment Drying Application

Table 1: Salient features of the project

Parameter Description

Solar Field Configuration 6 M95 paraboloid Dish Concentrators total of 570m2 of concentrator area

Solar Tracking Arrangements

Fully automated 2-axis tracking with tracking receiver

Solar Field Working Fluid Thermic Oil

Heat Transfer Equipment Thermic Oil-to-Air Heat Exchanger

Inlet Temperature of Air 25°C–30°C

Outlet Temperature of Air Peak 120°C

Air Flow Rate Fixed at 55,000 kg/day

Average Daily Energy Yield Upto 15 lakh kcal/day

12 | SUN F CUS | July–September 2016

SUN F CUS |July –September 2016| 1514 | SUN F CUS | July–September 2016

Case StudyFeature 2

COMPOUND PARABOLIC CONCENTRATORS USED FOR INDUSTRIAL PROCESS HEATING IN KANDLAJatin Joshi1, Satish Shah2 and Deepak Gadhia3

1 MD, VCare Global, Vadodara; Email: jatin@vcare-global.com

2 Technical Adviser, VCare Global, Vadodara; Email: satish.shah@vcare-global.com

3 Trustee & Director-MSA Renewtech Foundation & Mentor to VCare Global, Vadodara; Email: deepak.gadhia@greenashram.org

VCare Global is a Vadodara-based engineering company which aims to utilize solar

energy for industrial, commercial, and residential applications to provide sustainable and enviro-friendly solutions.

VCare Global is committed to promote renewable technologies in industries. Traditionally, the industrial sectors are largely dependent on conventional fuels to meet their heating applications. Since its establishment in 2005, VCare Global has been researching, developing, and implementing affordable novel solutions of renewable and clean energy for providing process heat and air-conditioning for the industrial, commercial, residential, and hospitality sector. One of such proven, highly efficient, and economical solar thermal technology is Compound Parabolic Concentrator (CPC). CPC is suitable for generating hot water up to 90°C–100°C. VCare Global has applied and commissioned CPC technology for hot water generation at Kandla free trade plant for a leading FMCG company—Hindustan Unilever Ltd.

Need for CPC SystemEarlier the process heating requirement at Hindustan Unilever’s Kandla plant (Picture 1) was met by diesel. The key concerns—the

costing of diesel, its contribution to environmental pollution, including global warming—were the key drivers that led the company to consider alternative cleaner solutions. Hindustan Unilever decided to switch over to solar technology for heating 20 kl of process water during one shift operation. The water is heated from 30°C to 85°C, accounting for 11 lakh Kcal.

To meet the heating requirements, VCare Global proposed a comprehensive solution, based on Compound Parabolic Concentrator technology. The solution comprised of 160 collectors providing a total aperture area of 480 m2.

The system has a primary circuit consisting of cold water storage,

cold water pumping to the CPC in series and parallel laid on three arrays and collecting the generated hot water in the hot water tank (Figure 1). The CPC was designed to give 11 lakh kcal per shift operation on an average basis. To achieve the desired temperature of 85°C on the secondary side, it was designed to raise the temperature of hot water up to 92°C in the primary circuit, using solar energy generated from CPC.

ObjectiveWhile India has abundant coal, it is of poor quality causing substantial harm to the environment. India has meagre clean fossil fuels like oil and natural gas. The country has no option except to adopt renewable forms of energy, such as solar, hydro, wind, and biogas/biomass.

PerformanceThe complete system logs the

daily temperature of the thermic

oil and air circuits and can also be

remotely monitored. The installed

CST system can deliver up to

15 lakh kcal/day on a clear sunny

day and is able to save up to 150 kg

SKO on a daily basis. The CST

system is also equipped with

various safety features for automatic

handling of contingencies as listed

in Table 2.

Table 2: Safety Features of MWS Solar Field™

Condition Solar Field Auto Action

High Wind Conditions Dishes in safety position by anemometer signal

Low Oil Flow Alarm indicators and defocusing of dishes

Low Oil Level Triple contingency design including automatic top up by drawing oil from overflow and expansion tanks; reverse flow condition prevention, U-loop configuration

High TemperatureConditions

Thermal storage or defocus of solar field as per equipment schedule

Low pressure Pump and circuit pressures linked by pressure switches to provide alarm

Intermittent CloudyConditions

Temporary defocus and refocus routines

Permanent Cloudy Conditions

Defocus and safety positions, Alarm indicators

Process Condition Auto detection of process status

Remote Monitoring Via GSM/GPRS

Emergency Condition Master Shutdown

ImpactA one of its kind project, MWS Solar Dish Concentrators has been successfully integrated for generating hot air through heat exchanger. The system is a classic example of successful integration of Concentrated Solar Thermal with fossil-fuel based industrial heating systems. The subsidy and support from the MNRE ensures that the system pays back within 4 years, thus, guaranteeing more than 20 years of emission free, zero-fuel process heating.

Picture 2: Pigment Drying Tunnel

Picture 1: CPC Collectors Installed at Hindustan Unilever, Kandla, Gujarat

Picture 3a: Initial Pigment Fed to Dryer Picture 3b: Final Pigment After Drying

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Case Study Feature 3

Leh-Ladakh, recognized as the Land of High Passes, is a high-altitude cold desert region of Jammu and Kashmir that extends from Kunlun mountain

range to the main great Himalayas to the south. A solar rich region, with an average Direct Normal irradiance (DNI) of 5.43 kWh/m2/day, Ladakh is a favourite place for solar thermal applications. There are some places in Leh-Ladakh, that are blessed with solar insolation of around 1,200 W/m2 . Along with the Ladakh Renewable Energy Development Agency (LREDA), the Ministry of New and Renewable Energy (MNRE), Government

of India, has implemented many solar projects for process heating, cooking, and water heating. Due to the elevated geography, maintenance and monitoring of such solar systems becomes essential. To address this issue, a team of MNRE, led by Mr Abhilakh Singh, General Manager, IREDA, visited Ladakh.

The delegation visited various solar thermal components, including the Greenhouses & CST-based systems in the district of Leh during 20–24, August 2016. During this visit, around 30 solar thermal installations were covered (Table 1).

SOLAR THERMAL TECHNOLOGIES FLOURISHING AT LEHKumar Abhishek1 and Abhilakh Singh2

Table 1: Total number of solar thermal components inspected, during the site visit in Leh region

System/Devices Allocated target (m2)

Target Achieved (m2 )

System Inspected (nos)

Steam Cooking System 10 1 7

Domestic Green House (DGH) 2,500 2,500 01

Commercial Green Houses (CGH) 750 300 11

Solar Water Heaters (SWH) 17,384 14,584 10

Dish Solar Cooker 4,500 2,250 20

Solar Dryers 500 Nil Nil

Ground Source Heat Pumps (GSHPs) 2 Demo Units Nil Nil

1 Technical Officer, MNRE; Email: abhishek.mnre@gmail.com2 General Manager, IREDA; Email: abhilakh@ireda.gov.in

Picture 1: Scheffler Dishes Installed at Lamdon Higher Secondary School (Girls Hostel)

Picture 2: Scheffler Dish Installed at Jamyang School

On a micro level, industries across the country face the problem of rising fuel costs compounded by regulatory edicts from the state environmental boards that are becoming stricter by the day. Cost reduction was certainly an objective for Hindustan Unilever and at the same time, being a steward of a clean environment.

ChallengesUnilever, the client of VCare requested them to offer a sustainable solution to offer the fuel savings and reduce its carbon-footprint. After exploring various technologies for solar process heating which included Flat Plate Collectors, Evacuated Tube Collectors, Parabolic dishes, Parabolic Trough Concentrators and Fresnel Linear Concentrator.

T1

H1 M1

feed water

solar collector

head watertank

cold tank hot tank

T2 T3

P1

P2

92 C

37 C 30 C

85 C

outlet

inletPHC

Figure 1: System Schematic Diagram

VCare zoomed in on CPC as it was most suited of the technology for such application.

Space is a challenge for any Solar Thermal Heating system. The Kandla project was no exception. VCare Global mitigated the challenge by designing the layout of CPC panels in a most space-minimizing way.

The challenge was installation of system at site as soil conditions had to be analysed to determine type of civil foundation and work could be decided.

Another challenge was limited working time that was allowed at plant (only during daytime) and of course being monsoon many days of site work was delayed as civil work and insulation work could not be undertaken during that period but still the timeline had to be maintained.

User FeedbackThe Unilever team is satisfied with the system performance and the user-friendly control system provided with the PLC panel, and SCADA. With this, they can measure, control, monitor, and analyse the system performance.

SavingsThe client has started taking benefits by using the Solar Thermal Hot Water System of saving in daily diesel consumption at about 127 ltr/day and also reduction in CO

2 emission of about 126 Ton

CO2 per annum of 300 days

operation.

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Feature 3Feature 3

Picture 6: Inside View of the Commercial Greenhouse Village, Tikse; Owner, Phuntsog

Picture 5: Outside View of Commercial Greenhouse Village; Tikse, Owner; Phuntsog

Picture 3: The 3,000 LPD System Installed at Alpine Villa, Leh Picture 4: 500 LPD System in Pangong Lake at 3500 ft. above sea level

Solar Water Heating SystemsSolar water heaters are the most popular thermal

equipment in Leh and generally are the highest in

terms of solar installations.

The LREDA–LAHDC (Ladakh Autonomous Hill

Development Council) has set an installation target

of around 17,584 m2 solar water heating systems

for the financial year 2015–16. Till date, LREDA has

successfully achieved and installed 14,584 m2 for this

current financial year.

The team inspected 10 solar water heating systems

and interacted with the beneficiaries, following which

the performance of existing installations was found

satisfactory (Table 3).

Although some of the systems were 4–5 years old

performance of existing installations found satisfactory.

The demand of solar water heaters is very high in Leh

region, now MNRE has revised its target for current

financial year. A proposal for installation of solar water

heater of 15,600 sq. m is under consideration.

Table 2: Steam cooking system visited in Leh

Beneficiary Details CST Technology

Collector area(m2 )

Project Status

Lamdon Boys Higher Secondary School, Leh Scheffler 64 Under Implementation

Lamdon Girls Higher Secondary School, Leh Scheffler 64 Complete

Druk Padma Karpo Residential School through LAREDA Scheffler 64 Under Implementation

Jamyang School Scheffler 64 Completed

Central Institute of Buddhist Studies Scheffler 64 Under Implementation

Govt. Residential School, Tharuk Scheffler 64 Completed

Govt. Residential School, Nayoma/Diskit Scheffler 64 Completed

Govt. Residential School, Khaltsi Scheffler 64 Completed

Lamdon School, Shrey Scheffler 64 Completed

Steam Cooking SystemRecently, MNRE has sanctioned 9 steam cooking systems, each with an aperture area of 64 m2

(Pictures 1 & 2). It was found that six out of these nine

sites are either in the phase of completion or are under

developed. These projects can be summed up in Table 2.

Table 3: Status of the Solar Water Heating Systems

Location Capacity in LPD Status

Installation at Stock Palace, Leh 100 Working

Druk Padma Karpo Residential (Rancho School) Shey by (LREDA) 100 Working

Lamdom Higher Secondary School in Shey by (LREDA) 200 Working

Linshed Residential hostel Shey by (LREDA) 300 Working

Lamdom Higher Secondary School in Shey, donated by SOTRA nasa 1,000

Rest Point Tent, near Pangong Lake in Leh at 3500 ft. 1,000 Working

Lamdom Boys Higher Secondary School in Leh by LREDA 1,400 Working

Jamyang School in Leh by LREDA 2,000 Working

Alpine Villa in Leh by LREDA 3,000 Working

Food Point Tent near Pangong Lake in Leh at 3500 ft. 3,500 Working

Table 4: Details of Greenhouses Covered

Year of Installation

Type of Greenhouse

Location and Name of Owner

2011 Commercial Village: Tikse; Owner: Lobzang

2012 Commercial Village: Tikse; Owner: Phuntsog

2012 Commercial Village: Shey; Owner: Padma

2015 Commercial Village: Tikse; Owner: Thinles

2015 Domestic Location: Lamdon Model School, Shey, Leh, Ladakh

2015 Commercial Location: Druk Padma Karpo, Residential School (Rancho School)

2016 Commercial Village: Shey; Owner: Tsetan

2016 Commercial Village: Shey; Owner: Stanzen

2016 Commercial Village: Shey; Owner: Zangmo

2016 Commercial Location: Lamdon Boys High School

2016 Commercial Location: Lamdon Girls High School

2016 Commercial Village: Stok; Owner: Dokpa

GreenhousesLocated at an altitude of around 11,000 ft. above sea level, the temperature in Leh varies from 30°C–30°C and is extremely difficult to cultivate vegetation. So, greenhouses plays crucial role in the process of cultivation. The LREDA LAHDC has, so far, constructed 2,900 greenhouses in Leh. The demand for greenhouses (Pictures 5 & 6), especially the commercial greenhouses, in Leh is so high that the sanctioned 500 greenhouses as per the demand in 2016–17 is already completed, and the agency is planning to submit a new proposal for greenhouses to MNRE. During the visit, a total of 12 greenhouses were covered (Table 4) and their condition and performance was

found satisfactory.

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Figure 1: Open-loop Control

International Feature International Feature

Another inconvenience of the open loop control is the sun sensor: as an optical element, it is subject to dust soiling and reflections from external elements that would induce errors. Careful adjustment is required so that the reflected beam hits properly the receiver.

In contrast, other advantages of the open loop control (besides the ability to accurately track the sun during cloudy transients) are its capability of upgrading the program to include compensation of the structural bending as a function of the angle, or implementing a power ramp-up and ramp-down to avoid thermal stress of the receiver, or implementing a partial defocus tracking to avoid heat dumping, or an anti-freezing mode.

Atria Local ControllerAtria Smart Energy Solutions has designed and tested an open-loop local controller (Atria LOC) with two objectives in mind: (i) low cost and (ii) flexibility, enough to suit any need (current or future) of the parabolic trough collector

The computing hardware of the LOC is based on Microchip PIC24H series microcontrollers, with added peripheral to support RS232 and RS485 communications, thermocouple temperature reading, pulse width modulation for motor control, quadrature encoders from the slew drive sensors and other auxiliary devices such as DIP switches for selecting the MODBUS slave ID. The Printed Circuit Board (PCB) (see Picture 1) measures only 8x6 cm, and can be easily installed inside a common junction box For testing purposes an LCD screen and small joystick has been added for local control (see Picture 2).

The software programmed in the LOC is based on Finite State Machines, therefore no operating system is needed while achieving a true cooperative multitasking.

TestingA small Parabolic Trough Collector testing platform has been built and installed on the roof at Atria Smart Energy Solutions office for monitoring the operation (see Picture 3). 3D printed gears and a brushed 12 V DC motor with reduction gearbox are being used to measure the performance of the Atria LOC and the accuracy of the sun tracking. The DC motor is run using a full H-bridge MOSFETS which receives the PWM sent by the LOC and translates into a variable voltage power output. An digital inclinometer has been attached to the driven gear to communicate with the LOC via RS232 bus, and it gives an accuracy of 0.1°.

The testing platform includes a rod, parallel to the rotation axis, at a distance of 0.57 m, which projects a shadow on a scale so that angular deviations can be measured. A laptop with a small SCADA programmed for this application reads the position of the PTC and other parameters, such as the circuit temperature, time, and date with an internet time server (no GPS required).

Results and Future DeploymentThe tracking has been very good, with an accuracy of about + 0.1° despite some backlash of the gears.

The industrial version of the LOC will consist of more than 1000 units for the 10 MW CSP plant being developed by Atria Power in Karnataka. The complete LOC will include a switched power supply to get 24 Vdc from the 415 Vac network, and a power H-bridge driver.

With the flexibility that a custom LOC gives, Atria Smart Energy Solutions will be glad to study any automated sun tracking need in order to provide the best, cost-effective solution for Concentrated

Solar Power systems.

Picture 1: Atria LOC Prototype, PCB Side

Picture 2: Atria LOC in a Junction Box w/LCD Screen Driving a Small Parabolic Trough Simulator

Picture 3: General view of the Testing Platform, Prior to Relocating the LOC in a Junction Box

OPEN-LOOP TRACKING FOR PARABOLIC TROUGH COLLECTORS Carlos Tejada1

Concentrated Solar Power, especially with high concentration ratios on

small receivers, requires a good solar tracking. Combine it with a large mirroring area and you need an automated system to overcome the tedious and error-prone task of managing a hand-operated sun tracking. This automation control can be performed on either opened or closed loop.

Open-Loop TrackingAn open-loop controller (also called non-feedback) is a type of controller that computes its input into a system using only the current state and its mathematical model of the system.

In terms of sun tracking for concentrated thermal heat, the mathematical model is the solar equation, the inputs are mechanical actuators (one or two axis), and output is the concentrated beam into the receiver, as can be seen in Figure 1.

The solar equations are mathematical formulas that take the geographical position (latitude and longitude) and the current date/time of day as inputs, and gives the elevation and azimuth solar angles as output. These two

values are further processed with a rotation matrix to obtain the single axis angle position for a parabolic trough collector.

The mathematical formulas are computing-intensive, with many trigonometrical double-precision calculations and large look-up tables. The Global Positioning System is used which provides this information in real time with excellent accuracy and relatively cheap receivers. The air pressure and temperature also need to be accounted for sun’s refraction in the atmosphere, at low elevations.

The computing power required is very challenging for real-time applications. Earlier personal computers were used for this task despite the high cost, power consumption, and space required.

However, the development of powerful yet small and cheap microcontrollers changed the game. They can be programmed using high level compilers, with lots of memory, integrated peripherals,

and computing power exceeding 40 MIPS (millions of instructions per second).

Simply connecting a GPS receiver to a microcontroller will help us in open-loop tracking with high accuracy at a low cost.

Comparison with Alternative Tracking MethodsA closed-loop controller provides feedback on the output status, and uses the difference between the desired set-point and the actual position (also known as the ‘error’)

to change the output in order to reduce this error (see Figure 2).The easiest way of automated sun tracking can be performed by closing the control loop with a sun sensor. This method is simple, relatively cheap, and allows some margin for construction misalignment and drive tolerances. It can be implemented using only analog electronics, eliminating the need of programming algorithms.

However, the most obvious drawback to this system is how to track the sun during cloud transients. The system either stops tracking or starts moving back and forth.

Apparent sun positioncalculation

Electrical motors driven tocalculated position

Reflected beam hitting thetarget (hopefully)

1 Head of Instrumentation and Controls, Atria Smart Energy Solutions S.L.U., Spain; Email: carlos.tejada@atriapower.es

Figure 2: Closed-loop Control

Error betweencurrent position

and sunobservedposition

Reflected beamhitting the

target

Electricalmotors drivento counteract

the error

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Events Forthcoming Events

BANKERS’ MEET ON LOAN PROVISION FOR CONCENTRATING SOLAR TECHNOLOGIES

On the issue of providing loans to development of Concentrating Solar Technologies (CST), the senior public sector bank officials confirmed that better knowledge about CST technology and its various applications via trainings is the need of the hour. The scope of asset-based financing especially in the

case of capital subsidy availability from MNRE and UNDP/GEF was also discussed. The need of manufacturers to reach out to banks and help build capacity on CSTs was also discussed. Insight from bank officials was also sought to have better understanding on designing business models that would covered most risks judiciously.

WORKSHOPS ON CONCENTRATING SOLAR THERMAL TECHNOLOGIES IN INDUSTRIES

GEF and UNIDO in partnership with the MNRE are implementing a project on ‘Promoting business models for increasing penetrations and scaling up of solar energy’ under which a series of workshops and site visits are being organized. Four such workshops were organized in Hyderabad,

Kolkata, Jaipur, and Lucknow, to create awareness about the technology and its potential for application in the industrial sector. Wide participation and support from industry has been ensured through close cooperation with the State Nodal Agency Uttar Pradesh New and Renewable Energy Development Agency (UPNEDA) and Confederation of Indian Industries (CII) for the workshop. The workshop saw presentations from CST manufacturers showcasing technologies available in the market and their application, technical specifications of their system and some case studies based on their installations in the country. The workshops also saw huge participation and active interactive dialogue with the industry representatives across different sectors, giving tremendous boost to the possibilities of implementing CST projects in eastern India.

July 14-15, Kolkata

September 14-15, Hyderabad

July 28-29, Jaipur

July 21-22, Lucknow

FORTHCOMING EVENTS

NATIONAL INTERNATIONAL

Seminar on Concentrating Solar Thermal (CST) TechnologiesOctober 1–2, 2016 Abu Road, Rajasthan Website: http://www.india-one.net/index.html; Registration: infocshcenter@gmail.com

11th ISES EuroSun Conference 2016October 11–14, 2016 Palma de Mallorca, Spain Website: www.eurosun2016.org/

Intersolar India 2016 October 19–21, 2016 Mumbai, Maharashtra Website: www.intersolar.in/en/home.html

SolarPACES 2016October 11–14, 2016 Abu Dhabi, UAE Website: www.solarpaces-conference.org/home.html

3rd EnviroTech Asia 2016December 2–4, 2016 Gandhinagar, Gujarat Website: http://www.envirotechasia.com/

Solar Asset Management EuropeNovember 9–10, 2016 Milan, Italy Website: www.solarassetmanagementeu.com/home/#solar-asset-management-europe

2nd International Conference on Solar Energy PhotovoltaicDecember 17–19, 2016 Bhubaneswar, Odisha Website: http://www.kiit.ac.in/icsep2016/

10th International Concentrated Solar Thermal Power SummitNovember 9–10, 2016 Seville, Spain Website: http://www.csptoday.com/csp/

Energy Storage India 2017January 12–13, 2017 Mumbai, Maharashtra Website: http://www.esiexpo.in/

Solar Finance & Investment Southeast AsiaNovember 29–December 1, 2016 Bangkok, Thailand Website: http://seasia.solarenergyevents.com/

RE-INVEST 2017February 15–17, 2017 Gandhinagar, Gujarat Website: http://re-invest.in

ASEAN Energy Storage Congress & Expo 2016December 5–6, 2016 Kuala Lumpur, Malaysia Website: http://www.aseanenergystorage.com/